Can bettas live with endlers?

Verdict
Yes

Yes. Bettas and endlers get along in the same tank. Both are fine at 76–82°F. Plan on at least 5 gal.

BettaBetta76–82°F · pH 6.5–7.5 Endler's livebearerEndler's livebearer72–82°F · pH 7–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 76–82°Betta 76–82°Endler's livebearer 72–82°
The green band is the temperature range both can live in.
456789Both: 7–7.5Betta 6.5–7.5Endler's livebearer 7–8
The green band is the pH both tolerate.

Size to scale

Betta · 2.5 inEndler's livebearer · 1 in0"1"2"3"4"5"6"
Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

BettaEndler's livebearer
Temperature76–82 °F72–82 °F
pH6.5–7.57–8
Adult size2.5 in1.0 in
Minimum tank5 gal5 gal
TemperamentSemi-aggressivePeaceful
Swims atTopTop
GroupOne per tankGroups of 3+
DietCarnivoreOmnivore

Better tank mates for bettas

All betta tank mates

Better tank mates for endlers

All endler's livebearer tank mates

Questions

Can bettas live with endlers?

Yes. Bettas and endlers get along in the same tank. Both are fine at 76–82°F. Plan on at least 5 gal.

What temperature suits both bettas and endlers?

76–82 °F. Bettas need 76–82 °F, endlers need 72–82 °F.

What size tank do bettas and endlers need together?

At least 5 gal, set by the betta. Add space for each extra fish.